Wireless charging technologies have been widely applied to electronic devices, especially to portable electronic devices (mobile terminals, tablet computers, etc.), and have broad development prospect, because of its convenience of being not restricted by the wired charging cable connection.
A wireless charging receiving terminal at the electronic device side and a transmitting terminal of a wireless charging device carry out a close-range energy exchange. For the wireless charging standard Qi introduced by Wireless Power Consortium (referred to as WPC) in the form of electromagnetic induction, the wireless charging technology Power Matters Alliance (PMA) launched by Powermat, and the Alliance for Wireless Power (A4WP) technology created by WPC formed by Qualcomm Incorporated, Samsung and Powermat in the form of magnetic resonance, there are problems of electromagnetic conversion efficiency. That is, it is impossible to achieve the complete conversion of the transceiving energy, and the excess energy is often dissipated in the form of heat loss.
In order to reduce this dissipation and improve the efficiency, in a wireless charging technology in the form of electromagnetic induction in which the technology is relatively mature at present, in addition to the fact that the transmitting antenna board for wireless charging (the winding forms a plurality of concentric rings, and the ferrite substrate forms a flat board) and the receiving antenna board for wireless charging are basically the same in size and the distance therebetween is controlled in a range from 2 mm to 4 mm, a typical positioning manner such as a fixed and freely positioning manner is used. The fixed positioning manner usually increases, in the center of the ring, magnet for positioning the wireless charging receiving terminal and transmitting terminal. The freely positioning manner is to adopt a plurality of overlapped receiving antenna loops at the receiving terminal to ensure that the magnetic induction amount of different points in the effective range is basically uniform, thereby achieving the “free positioning”.
However, even if the positioning measure is taken, due to the difference in size of practical mechanical processing between the individual devices, when the electronic device is placed on the transmitting antenna board of the charger, though the transmitting board of the charger relatively evenly distributes the energy field, the fixed receiving board of the electronic device cannot be ensured to be located just right on the maximum point of the energy conversion efficiency of the transmitting board, and users often still need to move back and forth the electronic device (actually to match the position of the receiving antenna board of the electronic device and the position of the transmitting antenna board at the charger side) during practical use to find the highest efficiency point. The system interface of the electronic device also prompts the high point of charging efficiency to users based on the movement of the electronic device so that the user can complete the charging in a shorter time. Since a certain time loss is required for the adjustment and for the response of the charging system, the user experience is not very good.
In the case of the wireless charging technology in the form of electromagnetic induction, though the charging transmitting terminal and the charging receiving terminal may be located in a relatively distant and relatively free position of about 50 cm, since the transmitting terminal of the magnetic resonance field is in the form of an array of a plurality of continuous transmitting boards, the fixed receiving board of the electronic device cannot be ensured to be located just right on a particular transmitting board to achieve the maximum point of the energy conversion efficiency, and there are also some factors of loss.
There is no effective solution at present for the problems of wasting time and poor user experience caused by adjusting back and forth the electronic device in the process of wireless charging of the electronic device needing to be charged in the related art.